What is Medicare Part D?

Medicare Part D is a plan offered by a private insurer that helps cover prescription drug costs. You must be enrolled in Original Medicare Part A and/or Part B to be eligible.

Why do I need Medicare Part D?

If you take prescription drugs, you should consider Medicare Part D prescription drug coverage. Original Medicare (Parts A and B) doesn't cover most drugs. If you don't have a Medicare Part D plan or other drug coverage, you'll pay for your drugs out of your own pocket, which can really add up. Part D may help lower your prescription drug costs and help protect you against higher costs in the future.

What are my Part D options?

You have two options for Medicare Part D:

  • You can get Medicare Part D through a private insurance company that offers a Medicare Advantage with prescription drug (MAPD) plan. You must have Part A and Part B to join an MAPD plan.
  • Or you can get a stand-alone Part D prescription drug plan (PDP). You must have Medicare Part A and/or Part B to buy a PDP plan. If you choose an MAPD plan, you don't need Part D. It's already included.

Is every Medicare Part D plan the same?


Medicare Part D monthly premiums, copayments and deductibles vary from one insurer to the next. You will be able to tell if the drugs you take are covered by Medicare Part D by checking our formulary. The formulary is a list of approved drugs covered by your Part D plan. If you find your drugs are not covered, you may want to consider a different plan.

When am I eligible to enroll for Medicare Part D?

The best time to enroll for Part D is during your initial enrollment period:

  • The three months before you turn 65
  • The month of your birthday
  • The three months after you turn 65

If you decide to wait to enroll in Medicare Part D and you don't have "creditable coverage" (coverage as good as Original Medicare) – for instance from an employer or union – you could end up paying a late enrollment penalty. This late enrollment fee will be added to your monthly premium once you do enroll and will continue for as long as you have Medicare. You'll pay a fee based on the following calculation: 1% of the national base premium for that year for every month you were eligible but not enrolled.

Want to switch your Medicare Part D?

If you enroll in a Part D plan that doesn't work for you, you can switch to a different plan during the annual election period (AEP) each year from Oct. 15 - Dec. 7.

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